1. Field of the Invention
The present invention relates to a steering device which in particular is, when implementing tilt and telescopic adjustment, capable of strengthening a locked state thereof and allowing a tilt and telescopic adjustment operation in an unlocked state to be performed smoothly.
2. Description of the Related Art
In the related art, in order to increase the force of retaining the position of a steering wheel to the position after tilt adjustment, a structure in which a pressure-contact frictional force caused by an axial force of a lock bolt is increased by superimposing a plurality of friction members is employed. Structures of this type are disclosed in Japanese Examined Utility Model Application Publication No. S62-19483 and Japanese Unexamined Patent Application Publication No. 2006-298072. Japanese Examined Utility Model Application Publication No. S62-19483 and Japanese Unexamined Patent Application Publication No. 2006-298072 will be described briefly. In the following description, reference numerals attached to members are the same as those described in Japanese Examined Utility Model Application Publication No. S62-19483 and Japanese Unexamined Patent Application Publication No. 2006-298072.
Japanese Examined Utility Model Application Publication No. S62-19483 discloses a structure in which a plurality of plate members 27 is welded to a plurality of spacers 29 clamped between the plate members 27 to form double-disc clutches 23 and 25 (see FIG. 4 of Japanese Examined Utility Model Application Publication No. S62-19483). Japanese Unexamined Patent Application Publication No. 2006-298072 discloses a structure in which a friction plate 5 is fixed to a fixed side portion 1 of a fixed bracket A with an appropriate gap, and a friction washer 6 is inserted between the fixed side portion 1 and the friction plate 5. In this structure, a washer 15 is disposed on an outer surface 5a2 of the friction plate 5, and the friction plate 5 is clamped between the friction washer 6 and the washer 15 to thereby strengthen the force of fastening the friction plate 5.